Manual wheelchairs are comprised of a wheelchair frame that is supported on the ground by two front caster wheels and two rear drive wheels. The drive wheels are large relative to the front caster wheels. In lightweight wheelchairs, the drive wheels are configured to allow the user to propel and steer the wheelchair by rotating the large rear drive wheels by hand. The frame supports a seat for the wheelchair user. The frames are also configured for rigidity in order to provide a stable ride characteristic. Lightweight wheelchairs are also usually configured to be folded and disassembled for ease of transport.
In order to provide a rigid frame structure that can be folded, wheelchair frames for manual wheelchairs are commonly made of bent tubing of aluminum or other metals or alloys. The ability to fold the wheelchair is a competing design objective with creating frames that are rigid and lightweight. To aid in creating a rigid frame, wheelchairs often include opposed side frames connected by cross-braces. It would be advantageous if the arrangement and configuration of the cross-braces could be improved.